What can be done about chat?

I have not posted on these boards, but the games I have been in recently have driven me to do so.
In 5 of my last 7 games (and a lot more before that) I have been with extremely toxic players. The common themes:
* Scapegoating a player (blaming them for everything) so the whole team will join in and make the player feel awful
* Abusive language that is beyond belief. Telling players to kill themselves, wishing horrible illnesses on them or their family. One player even asked for an address so he could go round the players house and "kill them"
* Racism/Anti-Semitic/Homophopic terms or insensitivity towards disabilities (The one that tips me over the edge is always when people use autism as an abusive term)
All of the above is reportable, and I report it every time I see it. I call it out, and I tell the player it's not OK. Yet very rarely do I ever get told that my report has led to any action. And the horrendous behaviour continues, game after game.
It's league's responsibility to clean this up. It is not setting a good example to anyone about the game. I am currently in the situation where I love the game, but I hate the way people are treated by other players and that's not right. I know it's not the only community like this, but I really think that it's gone above and beyond.
To draw parallels to another game I play, iRacing. That community does not tolerate offensive chat. If someone so much as swears at another player they are at high risk of getting a chat restriction. League could learn from that.
So, is the challenge to great for league with the size of community, or are people generally OK with the way the league community is? Or have I just been unlucky in my games. I am on the verge of leaving league for the first time since it began because of the way the toxic aspects of the game seem to be going unchecked, which is a real shame, because the game itself is still unparalleled.
I'd like to put a positive spin on the above though. So short of my alternative approach (mute everyone, which isn't exactly helping those being bullied in chat) what other things can be done, maybe with the communities' help (tribunal anyone) to help bring the standard of chat up to a reasonable civilised level?

**Culture**
This board is all about fostering a healthy community in which discussions can revolve around player behavior systems or in-game suspensions. This includes topics on how the systems work, insight into why players were punished, and advice to help players improve moving forward.
> ***{{champion:126}} : I fight for a brighter tomorrow.***